1. Field of the Invention
The present invention relates to a substrate cleaning device and a substrate processing facility. More particularly, the present invention relates to a substrate cleaning device for cleaning a surface of a substrate (e.g., a glass substrate, etc.) for use in a display panel (e.g., a liquid crystal display panel of a liquid crystal display device, etc.), and a substrate processing facility comprising the substrate cleaning device.
2. Description of the Related Art
A typical liquid crystal display panel of a liquid crystal display device comprises a pair of transparent substrates (e.g., glass substrates, etc.). Thin film transistors (TFTs) are provided on a surface of one of the glass substrates, while a color filter is provided on a surface of the other glass substrate. The two glass substrates are attached to each other. Further, liquid crystal is sandwiched between the two glass substrates. In this manner, a liquid crystal display panel is produced.
In a manufacturing plant for liquid crystal display panels, glass substrates brought into the plant are supplied to various process steps after the surfaces thereof are cleaned. In the process steps, TFTs are formed on some of the glass substrates; a color filter is provided on some of the glass substrates; and the like. In each process step, the surface of the glass substrate is cleaned immediately before a certain process. Therefore, liquid crystal display panel manufacturing plants require a number of devices for cleaning the surfaces of glass substrates for use in liquid crystal display panels.
FIG. 9 is a front view showing an exemplary layout of an apparatus for processing glass substrates in a manufacturing plant of liquid crystal display devices. FIG. 10 is a plan view of the apparatus of FIG. 9.
A process apparatus 52 for carrying out predetermined processes on glass substrates is provided in a clean room 51. At an upper portion of the clean room 51, a plurality of hyper performance filters 53 are arranged in a horizontal direction. Each hyper performance filter 53 supplies clean air which flows down into the clean room 51.
In the clean room 51, the process apparatus 52 is provided with a loading apparatus 55 for transporting a glass substrate. The loading apparatus 55 transports a glass substrate in a linear direction along the process apparatus 52. A plurality of glass substrates to be used for liquid crystal display panels are brought into the clean room 51 where the glass substrates are housed in cassettes 40. The cassettes 40 are placed along a transporting direction (i.e., longitudinal direction) of the loading apparatus 55 and at a side of the loading apparatus 55. A cleaning device 56 for removing dust or the like from the glass substrate is provided adjacent to an end of the loading apparatus 55.
In each cassette 40, a plurality of glass substrates oriented horizontally are stacked vertically, spaced at appropriate intervals. The loading apparatus 55 is provided with a glass substrate suctioning hand having a pair of planar suctioning pads in parallel, which picks out a glass substrate from one of the cassettes 40 brought in along the side of the loading apparatus 55. The glass substrate suctioning hand can be moved vertically and longitudinally with respect to the loading apparatus 55.
A glass substrate which has been picked out by the glass substrate suctioning hand of the loading apparatus 55 is transported down to the cleaning device 56, in which the glass substrate is in turn placed. The surface of the glass substrate in the cleaning device 56 is cleaned by the cleaning device 56. The cleaned glass substrate is picked out from the cleaning device 56 by the glass substrate suctioning hand of the loading apparatus 55, and is transported to a predetermined position of the process apparatus 52.
An example of the glass substrate cleaning device 56 is disclosed in, for example, Japanese Laid-Open Publication No. 6-165960. In this device, a glass substrate to be cleaned is horizontally placed therewithin; pulsed waves of air are blown from a blowing nozzle to a surface (upper surface) of the glass substrate so that dust attached on the surface is removed; and the substrate is suctioned with a suctioning nozzle.
Recently, display panels comprise a glass substrate having a thickness of about 0.7 mm or less. As display panels are enlarged, the size of glass substrates brought into liquid crystal display panel manufacturing plants is increased up to a rectangular glass substrate having a side of about 1.3 m or more.
As described above, a number of cleaning devices 56 (FIGS. 9 and 10) are employed in liquid crystal display panel manufacturing plants. When glass substrates having a large area are handled, the cleaning device 56 needs to be enlarged so that the large-size glass substrate is horizontally placed therein. In this case, the cleaning device 56 disadvantageously occupies a large area. Since a liquid crystal display panel manufacturing plant requires a number of cleaning devices 56, the manufacturing plant requires a large area, possibly leading to a reduction in cost effectiveness.